Clinical and radiologic outcomes associated with the use of dynamic locking screws (DLS) in distal tibia fractures.

Abstract

The locked screw plate construct is often cited as being too rigid and prolonging healing in patients with metaphyseal fractures. The newly introduced dynamic locking screws (DLS) allow 0.2mm of axial motion, which should optimize healing near the near cortex. The purpose of this study was to analyze the clinical results of dynamic locking screws in distal tibia fractures. Data were acquired retrospectively. Only distal meta-diaphyseal tibia fractures treated with minimally invasive plate osteosynthesis and DLS were evaluated. Cortical and locking head screws were used for distal plate fixation to minimize soft tissue irritation over the medial malleolus, and DLS were used in the proximal plate fixation. Clinical and radiographic data were evaluated after 6weeks, 3months, 6months and 1year until fracture union. Twenty-two patients were treated with minimally invasive plate osteosynthesis and DLS. Six patients could not be evaluated because they returned to a foreign residence after the procedure. Fourteen fractures healed after a mean of 3.1months. Two fractures with insufficient reduction showed delayed union and healed after 9 and 9.5months, respectively. The callus index peaked at 6months. Dynamic fracture fixation might be a promising concept to reduce the frequency of metaphyseal non-unions in distal tibia fractures. But nevertheless, the dynamic construct cannot compensate for insufficient reduction.